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1.
Biochem Biophys Res Commun ; 551: 14-20, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33714754

RESUMO

The blood-brain barrier (BBB) is the most critical obstacle in the treatment of central nervous system disorders, such as glioma, the most typical type of brain tumor. To overcome the BBB and enhance drug-penetration abilities, we used angiopep-2-modified liposomes to deliver arsenic trioxide (ATO) across the BBB, targeting the glioma. Angiopep-2-modified calcium arsenite-loaded liposomes (A2-PEG-LP@CaAs), with uniformly distributed hydrodynamic diameter (96.75 ± 0.57 nm), were prepared using the acetate gradient method with high drug-loading capacity (7.13 ± 0.72%) and entrapment efficiency (54.30 ± 9.81%). In the acid tumor microenvironment, arsenic was responsively released, thereby exerting an anti-glioma effect. The anti-glioma effect of A2-PEG-LP@CaAs was investigated both in vitro and in vivo. As a result, A2-PEG-LP@CaAs exhibited a potent, targeted anti-glioma effect mediated by the lipoprotein receptor-related (LRP) receptor, which is overexpressed in both the BBB and glioma. Therefore, A2-PEG-LP@CaAs could dramatically promote the anti-glioma effect of ATO, as a promising strategy for glioma therapy.


Assuntos
Arsenitos/química , Cálcio/química , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Lipossomos/química , Lipossomos/farmacocinética , Peptídeos/química , Animais , Trióxido de Arsênio/química , Trióxido de Arsênio/farmacocinética , Arsenitos/farmacocinética , Barreira Hematoencefálica/metabolismo , Cálcio/farmacocinética , Ciclo Celular , Linhagem Celular Tumoral , Glioma/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus , Peptídeos/farmacocinética , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Nutr Res ; 85: 71-83, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33450668

RESUMO

Retrospective chart reviews have reported hypophosphatemia associated with elemental formula use in infants and children with systemic disease involving multiple diagnoses. The present study aims to evaluate the bioavailability of phosphorus from 2 commercial elemental formulas and to test our hypothesis of bioequivalence of the 2 products in healthy volunteers receiving gastric acid-suppressive medication. A single-center, double-blind, randomized, cross-over study was conducted in healthy volunteers with esomeprazole-induced hypochlorhydria. After a standardized low phosphorus meal followed by overnight fasting, subjects consumed 1 gram of phosphorus in a single oral dose of 1217 kcal of Product A (Neocate) or Product B (Elecare). The alternate product was given following a 1-week washout period. Blood and urine were collected at baseline and different time-points for up to 6 hours after product consumption. Area-under-the-curve (AUC) and peak values (Cpeak) for serum phosphate and calcium and urinary creatinine-corrected phosphate and calcium were assessed for bioequivalence of Products A and B. Results show that the geometric mean ratio (GMR) and 90% CI for serum phosphate were 1.041 (0.998-1.086) and 1.020 (0.963-1.080) for AUC0-360 and Cpeak, respectively, meeting the predetermined criteria for bioequivalence. Urinary creatinine-corrected phosphate followed a similar pattern after intake of Product A and B, but did not reach bioequivalence criteria (GMR: AUC70-370 = 1.105 (0.918-1.330); Cpeak = 1.182 (1.040-1.343)). Serum calcium concentrations (GMR: AUC0-360 = 1.002 (0.996-1.009); Cpeak = 0.991 (0.983-0.999)) and urinary creatinine-corrected calcium excretion (GMR: AUC70-370 = 1.117 (1.023-1.219); Cpeak = 1.157 (1.073-1.247)) demonstrated bioequivalence of the products. In conclusion, both elemental infant formulas showed equivalent serum phosphorus and calcium bioavailability in healthy volunteers even if combined with treatment with acid-suppressive medication.


Assuntos
Aminoácidos , Cálcio/farmacocinética , Carboidratos , Gorduras na Dieta , Fórmulas Infantis , Fosfatos/farmacocinética , Acloridria , Adulto , Fosfatase Alcalina/sangue , Aminoácidos/efeitos adversos , Disponibilidade Biológica , Glicemia/análise , Cálcio/sangue , Cálcio/urina , Carboidratos/efeitos adversos , Estudos Cross-Over , Gorduras na Dieta/efeitos adversos , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Fórmulas Infantis/efeitos adversos , Insulina/sangue , Masculino , Hormônio Paratireóideo/sangue , Fosfatos/sangue , Fosfatos/urina , Equivalência Terapêutica , Adulto Jovem
3.
Can J Physiol Pharmacol ; 99(3): 270-277, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32687730

RESUMO

Sodium deoxycholate (NaDOC) inhibits the intestinal Ca2+ absorption and ursodeoxycholic acid (UDCA) stimulates it. The aim of this study was to determine whether NaDOC and UDCA produce differential effects on the redox state of duodenal mitochondria altering the Krebs cycle and the electron transport chain (ETC) functioning, which could lead to perturbations in the mitochondrial dynamics and biogenesis. Rat intestinal mitochondria were isolated from untreated and treated animals with either NaDOC, UDCA, or both. Krebs cycle enzymes, ETC components, ATP synthase, and mitochondrial dynamics and biogenesis markers were determined. NaDOC decreased isocitrate dehydrogenase (ICDH) and malate dehydrogenase activities affecting the ETC and ATP synthesis. NaDOC also induced oxidative stress and increased the superoxide dismutase activity and impaired the mitochondrial biogenesis and functionality. UDCA increased the activities of ICDH and complex II of ETC. The combination of both bile acids conserved the functional activities of Krebs cycle enzymes, ETC components, oxidative phosphorylation, and mitochondrial biogenesis. In conclusion, the inhibitory effect of NaDOC on intestinal Ca2+ absorption is mediated by mitochondrial dysfunction, which is avoided by UDCA. The stimulatory effect of UDCA alone is associated with amelioration of mitochondrial functioning. This knowledge could improve treatment of diseases that affect the intestinal Ca2+ absorption.


Assuntos
Colagogos e Coleréticos/farmacologia , Ácido Desoxicólico/farmacologia , Duodeno/efeitos dos fármacos , Mitocôndrias/metabolismo , Ácido Ursodesoxicólico/farmacologia , Animais , Cálcio/farmacocinética , Colagogos e Coleréticos/farmacocinética , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ácido Desoxicólico/farmacocinética , Transporte de Elétrons , Absorção Intestinal/efeitos dos fármacos , Masculino , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Biogênese de Organelas , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Ácido Ursodesoxicólico/farmacocinética
5.
Mol Nutr Food Res ; 64(12): e2000031, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32386352

RESUMO

SCOPE: Blueberries are rich sources of bioactive polyphenols that may provide health benefits when consumed regularly, leading to their increased marketing as dietary supplements. However, the metabolic changes associated with consuming concentrated doses of purified polyphenols, as may be present in dietary supplements, are unknown, especially when considering the colonic metabolites formed. This study aimed to evaluate the pharmacokinetics of high doses of purified blueberry polyphenols. METHODS AND RESULTS: 5-month old, ovariectomized Sprague-Dawley rats are acutely dosed with purified blueberry polyphenols (0, 75, 350, and 1000 mg total polyphenols per kg body weight (bw)) and 45 Ca to measure calcium absorption. Blood and urine are collected for 48 h after dosing and phenolic metabolites measured via ultra high-pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The most prominent metabolites are colonically generated cinnamic and hippuric acids. Smaller amounts of other phenolic acids, flavonols, and anthocyanins are also detected. Most metabolites follow a dose-response relationship, though several show saturated absorption. Maximal metabolite concentrations are reached within 12 h for a majority of compounds measured, while some (e.g., hippuric acid) peaked up to 24 h post-dosing. Calcium absorption is significantly increased in the highest dose group (p = 0.03). CONCLUSION: These results indicate that increased doses of blueberry polyphenols induce changes in intestinal phenolic metabolism and increase calcium absorption.


Assuntos
Mirtilos Azuis (Planta)/química , Colo/efeitos dos fármacos , Polifenóis/farmacologia , Animais , Cálcio/farmacocinética , Colo/metabolismo , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Flavonoides/urina , Hipuratos/urina , Absorção Intestinal/efeitos dos fármacos , Ovariectomia , Fenóis/metabolismo , Fenóis/urina , Polifenóis/administração & dosagem , Polifenóis/análise , Ratos Sprague-Dawley
6.
Environ Geochem Health ; 42(1): 159-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31111334

RESUMO

This study was aimed at assessment of strontium and calcium mobility in soils and their accumulation with plants in the areas endemic for Kashin-Beck disease in Eastern Transbaikalia. The strontium and calcium mobility levels were determined using the method of sequential chemical extraction for 7 samples of meadow soils collected from the endemic region and 7 soil samples taken from conditionally control sites. To measure the Ca and Sr levels in the soil and plant samples, XRF analysis and AAS were used. The increased strontium level in the meadow soils of the endemic areas is accompanied by the element's higher mobility. The highest strontium yield was observed in the course of soil extraction using 1 M ammonium acetate, while the soils taken from the control sites gave lower amounts of the trace element. Furthermore, there is a positive correlation between the amount of the strontium extracted and its content in plants (r = + 0.86 - 0.98). At the sequential chemical extraction of calcium from the soils using the above method, the calcium yield was maximal in the ammonium acetate fraction (background sites) and in ammonium acetate and 6 M HCl fractions (endemic areas). The correlation between the amount of the calcium extracted in 1 M ammonium acetate and the macroelement levels found in plants was + 0.968. In addition, a peculiarly high accumulation of strontium in various willow species as compared to other meadow plants was revealed for the first time ever. Thus, the work introduces new data into the trace element biogeochemistry and environmental monitoring.


Assuntos
Cálcio/análise , Doença de Kashin-Bek , Plantas/metabolismo , Solo/química , Estrôncio/análise , Bioacumulação , Cálcio/farmacocinética , Monitoramento Ambiental/métodos , Pradaria , Humanos , Plantas/química , Sibéria , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Estrôncio/farmacocinética
7.
Mater Sci Eng C Mater Biol Appl ; 107: 110348, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761176

RESUMO

The differentiation of adult stem cells is usually performed in vitro, by exposing them to specific factors. Alternatively, one can use nanocarriers containing such factors, to be internalized by the cells. In this work we have reduce the size of those carriers to the nanoscale, developing bioactive silica nanoparticles with diameters under 100 nm, containing calcium and phosphate ions (SiNPs-CaP). These ions, once released inside adult stem cells, induce bone cell proliferation and differentiation, and stimulate the expression of bone-related proteins in a single dose administration. The SiNPs-CaP nanomaterials were prepared through a sol-gel approach, and the ions added with a post-synthesis functionalization method. The synthesized SiNPs-CaP have narrow size distribution, good colloidal stability, and show high levels of ion incorporation. Furthermore, the SiNPs-CaP have good cytocompatibility and promote the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSC), with alkaline phosphatase, osteopontin and osteocalcin production levels comparable to the ones obtained in standard osteogenic medium. The novel bioactive SiNPs-CaP are synthesized in a simple and fast manner and show the ability to promote osteogenic differentiation after a single dose administration, independently from external osteogenic inducers, showing great potential as carriers in bone tissue engineering applications.


Assuntos
Cálcio/administração & dosagem , Células-Tronco Mesenquimais/citologia , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Fosfatos/administração & dosagem , Fosfatase Alcalina/metabolismo , Cálcio/química , Cálcio/farmacocinética , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Liberação Controlada de Fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas/administração & dosagem , Osteocalcina/metabolismo , Osteogênese/fisiologia , Osteopontina/metabolismo , Tamanho da Partícula , Fosfatos/química , Fosfatos/farmacocinética , Dióxido de Silício/química
8.
Sci Rep ; 9(1): 14225, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578386

RESUMO

Lead is a naturally-occurring element. It has been known to man for a long time, and it is one of the longest established poisons. The current consensus is that no level of lead exposure should be deemed "safe". New evidence regarding the blood levels at which morbidities occur has prompted the CDC to reduce the screening guideline of 10 µg/dl to 2 µg/dl. Measurable cognitive decline (reduced IQ, academic deficits) have been found to occur at levels below 10 µg/dl, especially in children. Knowledge of lead pharmacology allows us to better understand its absorption and metabolization, mechanisms that produce its medical consequences. Based upon an original and very simplified compartmental model of Rabinowitz (1973) with only three major compartments (blood, bone and soft tissue), extensive biophysical models sprouted over the following two decades. However, none of these models have been specifically designed to use new knowledge of lead molecular dynamics to understand its deleterious effects on the brain. We build and analyze a compartmental model of lead pharmacokinetics, focused specifically on addressing neurotoxicity. We use traditional phase space methods, parameter sensitivity analysis and bifurcation theory to study the transitions in the system's behavior in response to various physiological parameters. We conclude that modeling the complex interaction of lead and calcium along their dynamic trajectory may successfully explain counter-intuitive effects on systemic function and neural behavior which could not be addressed by existing linear models. Our results encourage further efforts towards using nonlinear phenomenology in conjunction with empirically driven system parameters, to obtain a biophysical model able to provide clinical assessments and predictions.


Assuntos
Cálcio/farmacocinética , Chumbo/farmacocinética , Modelos Biológicos , Adulto , Envelhecimento/metabolismo , Transporte Biológico , Barreira Hematoencefálica , Reabsorção Óssea , Encéfalo/metabolismo , Cálcio/sangue , Criança , Humanos , Absorção Intestinal , Rim/metabolismo , Chumbo/sangue , Neurotoxinas/farmacocinética , Especificidade de Órgãos , Distribuição Tecidual
9.
Medicine (Baltimore) ; 98(40): e17421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577757

RESUMO

Regional citrate anticoagulation (RCA) was recommended as the first treatment option for adults by the Kidney Disease Improving Global Outcomes Kidney Foundation in 2012, for the characteristic of sufficient anticoagulation in vitro, but almost no anticoagulation in vivo. Traditionally, the substitute for RCA is calcium-free. This study investigated a simplified protocol of RCA for continuous hemofiltration (CHF) in children using a commercially available substitute containing calcium.An analytical, observational, retrospective study assessed 59 pediatric patients with 106 sessions and 3580 hours of CHF. Values before and after treatment were compared, including Na, ionic calcium (iCa) and HCO3 concentrations, pH, and the ratio of total calcium to iCa (T/iCa). In addition, in vivo and in vitro iCa, treatment time, sessions with continuous transmembrane pressure >200 mm Hg, and sessions with clotting and bleeding were recorded.The average treatment time was 33.8 ±â€Š10.1 hours. In vitro, 88.5% of iCa achieved the target (0.25-0.35 mmol/L), and in vivo, 95.4% of iCa achieved the target (1.0-1.35 mmol/L). There were 8 sessions with a transmembrane pressure >200 mm Hg and 3 sessions with filters clotted. After treatment, there were 2, 1, and 2 sessions with T/iCa > 2.5 (implying citrate accumulation), iCa < 0.9 mmol/L, and iCa > 1.35 mmol/L. No sodium disorders were recorded. There were fewer cases of acidemia and more cases of alkalemia after treatment compared to before.RCA-CHF with a substitute containing calcium and close monitoring could be a safe and effective treatment for children. In addition, the calcium test site in vitro and the adjustment of citrate should be given strict attention.


Assuntos
Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/terapia , Anticoagulantes/farmacocinética , Cálcio/farmacocinética , Ácido Cítrico/farmacocinética , Hemofiltração , Injúria Renal Aguda/etiologia , Anticoagulantes/administração & dosagem , Cálcio/administração & dosagem , Criança , Pré-Escolar , Ácido Cítrico/administração & dosagem , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
10.
Food Funct ; 10(10): 6429-6437, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31517352

RESUMO

This study developed a gastric-floating delivery system of calcium based on konjac glucomannan (KGM). The developed calcium tablets, consisting of one core layer coated with two barrier layers, were fabricated with a facile method. The role of KGM within the tablets was evaluated from characteristics including swelling behavior, hydrated gel properties, floating ability and release profiles of calcium (Ca). The results indicated that upregulating the KGM fraction accelerated the formation of a more compact gel network in gastric conditions, which prolonged both the floating lag time and floating duration, which resulted in a more sustained swelling behavior and a slower release of calcium. Among all the formulations, a core tablet containing 20% KGM (K20) was selected as the optimized one as it could quickly float up in 7.21 s, exhibited an almost linear release and obtained a release amount of 87.73% within 12 h. Finally, a comparison of in vivo calcium bioavailability between a KGM-based calcium tablet and a commercial calcium tablet (Caltrate®) was carried out by monitoring the serum calcium concentration after administration in rabbits. The results suggested that, after having the KGM-based calcium tablet, the changes of serum calcium levels were gentler due to a sustained-release property. The difference integral value between profile K20 and the baseline was 1.4358, larger than that of Caltrate® (1.1808), suggesting the higher absorption efficiency of KGM-based calcium tablets.


Assuntos
Amorphophallus/química , Cálcio/química , Composição de Medicamentos/métodos , Mananas/química , Extratos Vegetais/química , Animais , Disponibilidade Biológica , Cálcio/farmacocinética , Portadores de Fármacos/química , Coelhos , Solubilidade , Comprimidos/química , Comprimidos/farmacocinética
11.
Environ Sci Pollut Res Int ; 26(29): 30472-30484, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31444718

RESUMO

The supply of potassium (K) is a strategy to increase the tolerance of plants exposed to Cd toxicity. The aim of this study was to verify the influence of K on the growth and potential of Tanzania guinea grass (Panicum maximum Jacq. cv. Tanzania (syn. Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs)) for Cd phytoextraction as well as to evaluate nutritional attributes of this grass under conditions of Cd stress. The experiment was conducted in a randomized complete block design, using a 3 × 4 factorial arrangement, with three replications. Three rates of K (0.4, 6.0, and 11.6 mmol L-1) were combined with four rates of Cd (0.0, 0.5, 1.0, and 1.5 mmol L-1) in nutrient solution. Two plant growth periods were evaluated. The increase in K supply to plants exposed to Cd rates of up to 1.0 mmol L-1 caused increase in morphogenic and production attributes, as well as reduction in tiller mortality rate, in the second growth period. K concentrations (in both harvests) increased, while calcium and magnesium concentrations in the second harvest decreased with increasing Cd rates. The high availability of Cd (1.5 mmol L-1) in the nutrient solution caused decrease in relative chlorophyll index (RCI) in both harvests. The high supply of K to plants exposed to Cd resulted in high shoot dry mass production, reducing Cd concentration in the photosynthetic tissues (which means great tolerance of the plant) and increasing the accumulation of this metal in the shoots that can be harvested. Therefore, K increases the Cd phytoextraction capacity of Tanzania guinea grass.


Assuntos
Cádmio/isolamento & purificação , Cádmio/toxicidade , Panicum/efeitos dos fármacos , Potássio/farmacologia , Biodegradação Ambiental , Cádmio/farmacocinética , Cálcio/metabolismo , Cálcio/farmacocinética , Clorofila/metabolismo , Magnésio/metabolismo , Magnésio/farmacocinética , Panicum/fisiologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Potássio/farmacocinética , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/farmacocinética , Poluentes do Solo/toxicidade , Estresse Fisiológico
12.
Food Nutr Bull ; 40(3): 357-368, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31272212

RESUMO

BACKGROUND: In order to improve calcium status, fortified rice should have acceptable organoleptic properties of that food. OBJECTIVE: We aimed to assess whether home fortification of rice with slaked lime can increase calcium content of rice and whether this fortified rice is well tolerated in a nutritionally at-risk population. METHODS: This experimental study measured the calcium content of rice cooked with different concentration of lime and assessed the acceptability of fortified rice among 400 women and children. Each participant received fortified rice with one of five concentrations of lime (0, 2.5, 5, 7.5 or 10 gm per 500 gm of rice), with or without additional foods (lentil soup or fried green papaya). All participants were asked to score the organoleptic qualities on a hedonic scale. RESULTS: Analysis showed that rice calcium content increased in a dose- response manner with increased lime during cooking (76.03, 205.58, 427.55, 614.29 and 811.23 mg/kg for given lime concentrations). Acceptability of the meal was greater when additional foods were served with rice at all lime concentrations. In both groups, the 7.5M arm reported highest overall acceptability (children, 6.25; women 6.10). This study found significant association between overall acceptability (different concentrations of lime mixed rice; with/without additional foods) and between groups (women vs. children) (p value = < 0.001) where-as no association was found within groups. CONCLUSIONS: Lime-fortified rice can be feasible considering the calcium uptake of rice and organoleptic character. Further research on bioavailability can establish a solid foundation that will support design of an effective intervention to reduce calcium deficiency in this population.


Assuntos
Compostos de Cálcio/administração & dosagem , Cálcio/deficiência , Oryza , Óxidos/administração & dosagem , Bangladesh , Disponibilidade Biológica , Cálcio/análise , Cálcio/farmacocinética , Criança , Comportamento do Consumidor , Feminino , Alimentos Fortificados/análise , Humanos , Oryza/química , Sensação
13.
Environ Geochem Health ; 41(6): 2763-2775, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31172408

RESUMO

Manganese pollution to plants, soils, and streams from Mn-rich mine spoils is a global and persistent issue. Some former mining sites can be revegetated readily while others struggle to support plants. We explored Mn in plants and soils following 75 years of soil development and reforestation of a pine-northern hardwood forest at the former Betts Mine in western Massachusetts, USA. We studied soils on four Mn-rich mine spoils and at two control sites: an undisturbed location adjacent to the mine and on a non-Mn mineral bearing rock formation to determine if soil conditions have influenced the uptake of Mn and Ca by vegetation. We collected mid-season foliage from five dominant canopy trees and four common understory plants and excavated three soil pits at each site during July 2018. We found that control sites had lower total Mn (980 ± 140 µg g-1) in their soils than on the mine spoil sites (5580 ± 2050 µg g-1). Our soil data indicated that < 1% of total Mn was strong acid extractable at mine spoil soils and control sites. Surprisingly, the canopy trees established on mine spoils at the Betts Mine had equal to or lower foliar Mn concentrations (840 ± 149 µg g-1) and lower Mn/Ca ratios (0.3 ± 0.1 mol mol-1) than at control sites (1667 ± 270 µg g-1; 1.1 ± 0.2 mol mol-1), refuting our hypothesis of mine spoils driving highest Mn uptake. Soil pH and physicochemical properties suggest Mn primarily exists within primary minerals or form insoluble oxides at the mine spoil sites. Our results suggest higher Ca availability and pH in soils likely reduced Mn uptake and promoted reforestation of the mine spoils.


Assuntos
Cálcio/farmacocinética , Manganês/farmacocinética , Plantas/química , Poluentes do Solo/farmacocinética , Solo/química , Cálcio/análise , Concentração de Íons de Hidrogênio , Ferro/análise , Manganês/análise , Massachusetts , Mineração , Poluentes do Solo/análise , Árvores
14.
Nutrients ; 11(5)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064117

RESUMO

Hypovitaminosis D is becoming a notable health problem worldwide. A consensus exists among several different medical societies as to the need for adequate levels of vitamin D for bone and general health. The correct method by which to restore normal vitamin D levels is still a matter of debate. Although cholecalciferol remains the most commonly distributed form of vitamin D supplementation worldwide, several drugs with vitamin D activity are available for clinical use, and making the correct selection for the individual patient may be challenging. In this narrative review, we aim to contribute to the current knowledge base on the possible and appropriate use of calcifediol-the 25-alpha-hydroxylated metabolite-in relation to its chemical characteristics, its biological properties, and its pathophysiological aspects. Furthermore, we examine the trials that have aimed to evaluate the effect of calcifediol on the restoration of normal vitamin D levels. Calcifediol is more soluble than cholecalciferol in organic solvents, due to its high polarity. Good intestinal absorption and high affinity for the vitamin-D-binding protein positively affect the bioavailability of calcifediol compared with cholecalciferol. In particular, orally administered calcifediol shows a much shorter half-life than oral cholecalciferol. Most findings suggest that oral calcifediol is about three- to five-fold more powerful than oral cholecalciferol, and that it has a higher rate of intestinal absorption. Accordingly, calcifediol can be particularly useful in treating diseases associated with decreased intestinal absorption, as well as obesity (given its lower trapping in the adipose tissue) and potentially neurological diseases treated with drugs that interfere with the hepatic cytochrome P-450 enzyme system, resulting in decreased synthesis of calcifediol. Up to now, there has not been enough clinical evidence for its use in the context of osteoporosis treatment.


Assuntos
Calcifediol/uso terapêutico , Deficiência de Vitamina D/tratamento farmacológico , Osso e Ossos/metabolismo , Calcifediol/metabolismo , Cálcio/metabolismo , Cálcio/farmacocinética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos
15.
Dalton Trans ; 48(17): 5735-5740, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30972392

RESUMO

At present, though calcium (Ca) reagents with high calcium contents are widely synthesized, their wide application is limited due to their low absorption rates and poor bioavailability. Here we use a carboxymethyl cellulose (CMC) derivative with high water solubility and biocompatibility as a ligand to bind Ca2+. The resulting CaCMC complex exhibits remarkable solubility and absorbability under both basic and acidic conditions as well as in stomach mimicking and the gastrointestinal tract. Importantly, this Ca reagent shows high in vivo calcium bioavailability. Data from osteoporosis mouse models show that the CaCMC complex is superior to calcium carbonate in the treatment of osteoporosis. Therefore, the resulting CaCMC complex is used as a new, highly effective and desirable Ca supplement for daily life and clinical applications.


Assuntos
Materiais Biocompatíveis/farmacocinética , Cálcio/metabolismo , Cálcio/uso terapêutico , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacocinética , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Disponibilidade Biológica , Cálcio/administração & dosagem , Cálcio/farmacocinética , Carboximetilcelulose Sódica/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
16.
J Clin Apher ; 34(4): 490-494, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30673128

RESUMO

PURPOSE: During a national shortage of calcium gluconate, we switched to calcium chloride for routine supplementation for peripheral blood stem cell (PBSC) collections. Subsequently, we analyzed the postprocedure ionized calcium level, as we aimed for an equivalent result compared to before the shortage. METHODS: Pharmacy representatives helped us to find an "equivalent" substitute for calcium gluconate at 46.5 mEq in 500 mL normal saline, infused at 100 mL/hour. After instituting a presumably comparable protocol using calcium chloride (40.8 mEq in 250 mL normal saline at a rate of 100 mL/hour), we reviewed ionized calcium results post-PBSC procedures to compare with those obtained with calcium gluconate. Having noticed a difference in the mean values, we adjusted the rate of calcium chloride to reach our desired outcome. RESULTS: Twenty-seven procedures were analyzed on 15 unique patients. We used the Spectra OPTIA with a whole blood: anticoagulant ratio of 13:1. Ionized calcium levels post-PBSC collection with the first calcium chloride protocol were significantly higher (P = 0.003) in nine patients treated. Subsequently, we decreased the calcium chloride infusion rate to 75 mL/hour and achieved similar mean levels to calcium gluconate (P = 0.382). CONCLUSION: Changes in replacement fluids for apheresis procedures can be complex, particularly when dealing with electrolytes that could be clinically significant at critically high or low levels. Once we recognized the need to take into account the amount of elemental calcium infused, we achieved the desired postprocedure ionized calcium results. This study can serve as a lesson for future shortages of infusions used during apheresis procedures.


Assuntos
Gluconato de Cálcio/provisão & distribuição , Cálcio/administração & dosagem , Citaferese/métodos , Cálcio/farmacocinética , Cloreto de Cálcio/administração & dosagem , Humanos , Células-Tronco de Sangue Periférico/citologia
17.
Calcif Tissue Int ; 104(3): 301-312, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30390108

RESUMO

Menopause is associated with bone loss. Prebiotics increase Ca, inorganic phosphorus (Pi), and Mg absorption, improving bone health. These increases would supply an extra amount of minerals, decreasing bone resorption and possibly reversing ovariectomy-induced bone loss. The present experimental study sought to evaluate the effect of adding a prebiotic GOS/FOS® mixture to a normal or a low Ca diet on Ca, Pi, and Mg absorption, in osteopenic rats. Four groups of n = 8 rats each were OVX, and 8 rats were SHAM operated. All rats were fed a commercial diet for 45 days. They were then fed one of the following diet for 45 days: C-0.5%: SHAM fed AIN 93 M containing 0.5%Ca; O-0.5% and O-0.3%: OVX rats fed AIN 93 M, containing 0.5% or 0.3%Ca, respectively; GF-0.5% and GF-0.3%: OVX rats fed AIN 93 M, containing 0.5% or 0.3%Ca+ 2.5% GOS/FOS®, respectively. At the end of the experimental time point, Ca, P, and MgAbs% was significantly higher in GF-0.5% and GF-0.3% as compared to the remaining groups (p < 0.01). Irrespective of diet Ca content, CTX decreased whereas femur Ca and P content, tibia BV/TV and GPC.Th, lumbar spine and proximal tibia BMD, bone strength, bone stiffness, and elastic modulus increased in the GF-0.5% and GF-0.3% groups as compared to O-0.5% and O-0.3%, respectively (p < 0.05). This prebiotic mixture would be a useful tool to prevent the increase in bone loss associated with menopause and aging.


Assuntos
Doenças Ósseas Metabólicas/metabolismo , Osso e Ossos/efeitos dos fármacos , Cálcio da Dieta , Dieta , Absorção Intestinal/efeitos dos fármacos , Oligossacarídeos/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/patologia , Osso e Ossos/fisiologia , Cálcio/deficiência , Cálcio/metabolismo , Cálcio/farmacocinética , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/farmacocinética , Dieta/métodos , Suplementos Nutricionais , Feminino , Frutose/química , Frutose/farmacologia , Galactose/química , Galactose/farmacologia , Oligossacarídeos/administração & dosagem , Ovariectomia , Ratos , Ratos Wistar
18.
Food Funct ; 9(11): 5707-5714, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30311619

RESUMO

Wheat bread is a widely consumed food and is suitable for the introduction of functional ingredients. The aim of this work was to study the effects of bread with garlic and resistant starch as a fiber source on physiological, metabolic, and functional parameters using an in vivo Wistar rat model. Rats were fed with three diets: a control diet prepared according to the American Institute of Nutrition (C), and two semisynthetic diets containing wheat bread (B) and wheat bread with garlic, resistant starch and calcium citrate (BGR). Fresh feces were weighed and lactobacilli (L) and Enterobacteriaceae (E) were analyzed at different times: 1, 20, 45 and 60 days. The pH of the caecal content was recorded and at the end of the study changes in the bone mineral density of total skeleton (ts BMD), femur (F-BMD), spine (S-BMD) and tibia (T-BMD) were determined. Lipoprotein profile was assessed, atherogenic indexes were calculated and malonaldehyde content was measured in the serum and liver. In relation to gut microbiota, the BGR group showed an increase in the L/E ratio with respect to the other groups which was correlated with a lower cecal pH. Besides, the BGR group presented lower weight and a more favourable metabolic profile. In relation to bone measurements, the BGR group presented higher values of ts BMC, ts BMD, F-BMD, and T-BMD than the B group. Thus, bread with resistant starch, garlic and calcium citrate showed a prebiotic effect increasing calcium bioavailability and deposition in bones, compared with wheat bread. The observed beneficial health effects allow us to consider the design of healthier breads.


Assuntos
Pão/análise , Cálcio/farmacocinética , Alho , Amido/química , Triticum/química , Animais , Disponibilidade Biológica , Densidade Óssea , Cálcio/análise , Colesterol/sangue , Enterobacteriaceae/isolamento & purificação , Fezes/química , Fezes/microbiologia , Manipulação de Alimentos , Microbioma Gastrointestinal , Lactobacillus/isolamento & purificação , Masculino , Malondialdeído/sangue , Ratos , Ratos Wistar , Triglicerídeos/sangue
19.
Environ Sci Pollut Res Int ; 25(36): 36328-36340, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30368704

RESUMO

Chinese flowering cabbage is a commonly consumed vegetable that accumulates Cd easily from Cd-contaminated soils. Cultivations of low-Cd cultivars are promising strategies for food safety, but low-Cd-accumulating mechanisms are not fully elucidated. To address this issue, 37 cultivars were screened to identify high- and low-Cd cultivars upon exposure to sewage-irrigated garden soil pretreated with different Cd concentrations (1.81, 2.90, and 3.70 mg kg-1dry soil). The results showed that shoot Cd concentrations differed among the cultivars by maximum degrees of 2.67-, 3.71-, and 3.00-fold under control and treatments, respectively. Soil-pot trial and hydroponic trial found no significant difference in Cd and Ca mobilization, uptake, and transport ability by root per weight between high- and low-Cd cultivars. Interestingly, a stable R/S ratio difference among cultivars (p < 0.01) was observed, and the cultivar variation of Cd accumulation in shoots was mainly dependent on their R/S ratios. R/S ratio was also statistically positively associated with Cd and Ca accumulation in high- and low-Cd cultivars (p < 0.05), both in soil and hydroponics culture. This was mainly due to the lower root biomass of low-Cd cultivars resulted in lower total release of root exudates, lower total Cd and Ca mobilization in rhizosphere soil, and lower total Cd and Ca uptake and transport. The higher shoot biomass of low-Cd cultivars also has dilution effects on Cd concentration in shoot. Overall, low R/S ratio may be regarded as a direct and efficient indicator of low Cd accumulation in the shoot of Chinese flowering cabbage. These findings provided the possibilities to screening low-Cd cultivars using their R/S ratio.


Assuntos
Brassica/metabolismo , Cádmio/farmacocinética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Poluentes do Solo/farmacocinética , Brassica/efeitos dos fármacos , Cádmio/análise , Cálcio/farmacocinética , Inocuidade dos Alimentos , Hidroponia , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Rizosfera , Solo , Poluentes do Solo/análise
20.
Matern Child Nutr ; 14 Suppl 3: e12649, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30332539

RESUMO

Undernutrition resulting from inadequate access to high-quality, nutritious food is a widespread issue in sub-Saharan Africa impacting the health and survival of mothers and their children. Inadequate dietary intake leads to a deficiency in nutrients including calcium, required for growth and physiological functioning. This study investigated the potential of increasing dietary calcium intake by the addition of heat-treated ground eggshell to locally prepared food. A mixed methods approach of literature review, Delphi expert survey and focus group discussions with women of childbearing age in rural Tanzania, were used to assess the practicality, safety, and acceptability of consumption of ground eggshell. Chicken eggshell has high calcium content (380 mg of calcium/gram) and bioavailability comparable to calcium carbonate (~39%) with 1 g sufficient to provide one half of a sub-Saharan African adult female's dietary calcium needs. Salmonella was indicated as the most likely threat to human health through eggshell consumption. Experts agreed that eggshells boiled for 10 min when preparing hard-boiled eggs with a further 20 min cooking of crushed eggshell in staple foods would eliminate identified egg-associated pathogens. Five focus groups (n = 46) indicated eggshells were perceived as waste. However, there was an indication of general acceptance of the approach and a willingness to consider the incorporation of ground eggshells into their diets. Development of suitable communication methods are required to convey benefits and safe preparation methods. Ground eggshell could be a highly equitable method of increasing calcium intakes across rural sub-Saharan Africa where calcium intake is low and village poultry ownership common.


Assuntos
Casca de Ovo , População Rural , Adolescente , Adulto , África Subsaariana , Animais , Disponibilidade Biológica , Cálcio/análise , Cálcio/deficiência , Cálcio/farmacocinética , Cálcio da Dieta/administração & dosagem , Galinhas , Criança , Pré-Escolar , Culinária/métodos , Casca de Ovo/química , Feminino , Inocuidade dos Alimentos/métodos , Humanos , Lactente , Recém-Nascido , Gravidez , Recomendações Nutricionais , Tanzânia
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